Home-range size and habitat use of the introduced snapping turtle (Chelydra serpentina) were examined in an agricultural landscape of the Inbanuma Basin, central Japan. Twenty-eight subadult and adult turtles were tracked in 2002 and 2003 using radio telemetry. Home-range size did not significantly differ between sexes and was not affected by tracking period or the body size. Mean home-range sizes estimated using 50% kernel, 95% kernel, and maximum stream length were 0.9 ha, 3.9 ha, and 393 m, respectively. Habitat used by large turtles during the active season was restricted to the stream. Smaller turtles tended to use agricultural areas, such as paddy fields and ditches. The frequency of the stream use was low during the overwintering period. Considering that the adult mortality greatly affects population dynamics, introduced snapping turtles could be eradicated by trapping in streams.

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Litoria megalops sp. nov. from mountain torrents in Papua Province, Indonesia is described. It is most similar to L. micromembrana from which it is distinguished by its smaller size (male SVL: 24.6–27.5 vs 31.7–35.5 mm), exceptionally large and prominent eyes, and conical tubercles on the dorsum. The advertisement call of the new species is a short pulse train with 7–10 pulses per call and lasting 0.9–1.3 s. The new species was found at night on low vegetation along torrents in closed-canopy lower montane rainforest.

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We experimentally examined the anti-predator behaviors of tadpoles of the Japanese tree frog, Hyla japonica, to chemical cues released by a cyprinid fish, Gnathopogon elongatus elongatus, and a dragonfly nymph, Anax parthenope julius. Tadpoles exposed to these chemical cues exhibited a similar reduction in activity level. In the presence of the fish chemical cues, however, the tadpoles spent more time in the bottom water layer compared to controls, but did not change their microhabitat choice in the presence of dragonfly nymph chemical cues. These findings suggest that tadpoles of H. japonica have predator-specific behaviors in response to chemical cues from different predators with differential foraging strategies.

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Body size and age structure were studied for two breeding populations of the salamander, Hynobius tokyoensis, in the southern Kanto plain of Honshu, Japan. The mean snout-vent lengths (SVLs; measured from the tip of snout to the posterior end of cloaca) of males and females were 64.1 and 66.5 mm at Habu in Tokyo, and 63.1 and 65.3 mm at Isumi in Chiba prefecture, respectively. The differences in SVL were not significant between sexes or populations. The breeding adults, successfully aged by skeletochronology using phalanges, were 4-21 years old. The median age was significantly older in the Habu population (eight years) than in the Isumi population (five years), and the age at first reproduction estimated from the age at which the growth of individuals was greatly retarded was two to six years. The modal age at first reproduction was four years for both sexes in both populations except for males at Isumi (three years). In the latter, age at first reproduction was significantly younger than in the others. We discuss the ecological significance of interpopulational variation in age structure clarified by skeletochronology.

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Sexual dimorphism was examined in a population of the colubrid snake, Dinodon semicarinatum, from the northern part of Okinawajima Island. This snake exhibited a prominent male-larger sexual size dimorphism (SSD), and this was considered to have resulted from male-male combat for mating opportunity. The size of the head relative to snout-vent length was significantly larger in females than in males, suggesting that segregation for differential food items between sexes, often considered the major cause of SSD in snakes, does not account for the distinct SSD in D. semicarinatum. Patterns and causes of sexual dimorphism in other characters are also presented and discussed.

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The first record of Goniurosaurus luii from Vietnam is reported herein. The specimen is a female and the largest member of the species known to date. This brings the total number of Goniurosaurus in Vietnam to three.

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Phelsuma laticauda is recorded from Moorea, French Polynesia, for the first time on the basis of a hatchling specimen collected from the westernmost tip of the island in early October 2006. A much larger individual was also observed in the same area, but was not captured. These, as well as information with photographs from an inhabitant of the island regarding observations of similar geckos in 2003, strongly suggest a recent artificial introduction of this prominent gecko to Moorea and its establishment as a breeding population at least in the western part of this island.

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